kernel/drivers/net/ethernet/qualcomm/qca_7k.c

   1 /*
   2  *
   3  *   Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.
   4  *   Copyright (c) 2014, I2SE GmbH
   5  *
   6  *   Permission to use, copy, modify, and/or distribute this software
   7  *   for any purpose with or without fee is hereby granted, provided
   8  *   that the above copyright notice and this permission notice appear
   9  *   in all copies.
  10  *
  11  *   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
  12  *   WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  13  *   WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  14  *   THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
  15  *   CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  16  *   LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  17  *   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  18  *   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  19  *
  20  */
  21
  22 /*   This module implements the Qualcomm Atheros SPI protocol for
  23  *   kernel-based SPI device.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/module.h>
  28 #include <linux/moduleparam.h>
  29 #include <linux/spi/spi.h>
  30 #include <linux/version.h>
  31
  32 #include "qca_7k.h"
  33
  34 void
  35 qcaspi_spi_error(struct qcaspi *qca)
  36 {
  37         if (qca->sync != QCASPI_SYNC_READY)
  38                 return;
  39
  40         netdev_err(qca->net_dev, "spi error\n");
  41         qca->sync = QCASPI_SYNC_UNKNOWN;
  42         qca->stats.spi_err++;
  43 }
  44
  45 int
  46 qcaspi_read_register(struct qcaspi *qca, u16 reg, u16 *result)
  47 {
  48         __be16 rx_data;
  49         __be16 tx_data;
  50         struct spi_transfer *transfer;
  51         struct spi_message *msg;
  52         int ret;
  53
  54         tx_data = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_INTERNAL | reg);
  55
  56         if (qca->legacy_mode) {
  57                 msg = &qca->spi_msg1;
  58                 transfer = &qca->spi_xfer1;
  59                 transfer->tx_buf = &tx_data;
  60                 transfer->rx_buf = NULL;
  61                 transfer->len = QCASPI_CMD_LEN;
  62                 spi_sync(qca->spi_dev, msg);
  63         } else {
  64                 msg = &qca->spi_msg2;
  65                 transfer = &qca->spi_xfer2[0];
  66                 transfer->tx_buf = &tx_data;
  67                 transfer->rx_buf = NULL;
  68                 transfer->len = QCASPI_CMD_LEN;
  69                 transfer = &qca->spi_xfer2[1];
  70         }
  71         transfer->tx_buf = NULL;
  72         transfer->rx_buf = &rx_data;
  73         transfer->len = QCASPI_CMD_LEN;
  74         ret = spi_sync(qca->spi_dev, msg);
  75
  76         if (!ret)
  77                 ret = msg->status;
  78
  79         if (ret)
  80                 qcaspi_spi_error(qca);
  81         else
  82                 *result = be16_to_cpu(rx_data);
  83
  84         return ret;
  85 }
  86
  87 int
  88 qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value)
  89 {
  90         __be16 tx_data[2];
  91         struct spi_transfer *transfer;
  92         struct spi_message *msg;
  93         int ret;
  94
  95         tx_data[0] = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_INTERNAL | reg);
  96         tx_data[1] = cpu_to_be16(value);
  97
  98         if (qca->legacy_mode) {
  99                 msg = &qca->spi_msg1;
 100                 transfer = &qca->spi_xfer1;
 101                 transfer->tx_buf = &tx_data[0];
 102                 transfer->rx_buf = NULL;
 103                 transfer->len = QCASPI_CMD_LEN;
 104                 spi_sync(qca->spi_dev, msg);
 105         } else {
 106                 msg = &qca->spi_msg2;
 107                 transfer = &qca->spi_xfer2[0];
 108                 transfer->tx_buf = &tx_data[0];
 109                 transfer->rx_buf = NULL;
 110                 transfer->len = QCASPI_CMD_LEN;
 111                 transfer = &qca->spi_xfer2[1];
 112         }
 113         transfer->tx_buf = &tx_data[1];
 114         transfer->rx_buf = NULL;
 115         transfer->len = QCASPI_CMD_LEN;
 116         ret = spi_sync(qca->spi_dev, msg);
 117
 118         if (!ret)
 119                 ret = msg->status;
 120
 121         if (ret)
 122                 qcaspi_spi_error(qca);
 123
 124         return ret;
 125 }
 126
 127 int
 128 qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
 129 {
 130         __be16 tx_data;
 131         struct spi_message *msg = &qca->spi_msg1;
 132         struct spi_transfer *transfer = &qca->spi_xfer1;
 133         int ret;
 134
 135         tx_data = cpu_to_be16(cmd);
 136         transfer->len = sizeof(tx_data);
 137         transfer->tx_buf = &tx_data;
 138         transfer->rx_buf = NULL;
 139
 140         ret = spi_sync(qca->spi_dev, msg);
 141
 142         if (!ret)
 143                 ret = msg->status;
 144
 145         if (ret)
 146                 qcaspi_spi_error(qca);
 147
 148         return ret;
 149 }